Rotational casting machine

ABSTRACT

The disclosure is of a rotational casting machine capable of functioning continuously, comprising a rotary assemblage with four or more arms supporting moulds or mould-rotating devices, a charging station, a heating station, and at least two cooling stations.

llnited States Patent [1 1 Winning Nov. 27, 1973 [54] ROTATIONAL CASTINGMACHINE 2,957,202 10/1960 Rekettye 425/430 x 3, 89,1 9 197 W b k l. [76]inventor: Guy Winning, Hegenhe1m, France 6 91 2 est we at 8 425/429 x221 Filed: Feb. 14, 1972 Primary Examiner-H. A. Kilby, Jr. [21] Appl225916 Attorney-4min S. Thompson et al.

[30] Foreign Application Priority Data Jan. 13, 1972 France 7201648 [57]ABSTRACT [52] US. Cl. 425/174.4, 425/430 [51] Int. Cl B29h 3/00 Thedisclosure is of a rotational casting machine capa- [58] Field of Search425/ 1744, 174, 429, ble of functioning continuously, comprising arotary 425/430 assemblage with four or more arms supporting moulds ormould-rotating devices, a charging station, a heat- [5 6] ReferencesCited ing station, and at least two cooling stations.

UNITED STATES PATENTS 2,681,472 6/1954 Rempel 425/430 3 Claims, 2Drawing Figures PATENTEDHBY27 1915 3; 775,036

SHEET 1 BF 2 ROTATIONAL CASTING MACHINE INTRODUCTION AND BACKGROUND OFTHE INVENTION This invention relates to rotational casting machines forcasting synthetic plastics materials or analogous materials, and refersmore particularly to machines with rotary assemblages capable offunctioning continuously.

In the known machines of this kind generally there are provided threeproduction stations disposed upon a circle about the centre of whichthere turns a rotary assemblage equipped with three arms allowing thecharges to pass without interruption from one station to another. Inorder to improve the smoothness of production there have likewise beenused such machines with four stations and comprising two heating stages.

Nevertheless all these machines present various disadvantages which arenot negligible. In practice it is more and more necessary and useful, inorder to meet the requirements of manufacture with new plasticsmaterials or compounds to effect, for the same moulding, severalchargings of materials with the necessity of indexing the rotaryassemblage, for each charging, to the station provided for this purpose.It has been attempted to solve this problem by providing a rearwardsreturn of the rotary assemblage, a solution which nevertheless implies,in order to avoid a reheating in the furnace of the articles remainingat the cooling station, that the said heating stations with furnacesremain open, thus involving excessive losses of heat.

On the other hand, in the known machines the changes of moulds and ofarms are lengthy and cannot be integrated into the normal cycle ofoperation and therefore necessitate interruptions of manufacture whichare often prolonged and always unproductive.

In order to alleviate these disadvantages the present invention has forits object a rotational casting machine thanks to which it is possibleon the one hand to effect several chargings without returning the rotaryassemblage towards the rear, without heat losses, and on the other handto double the period of cooling, all whilst maintaining the same rhythmof production and, f1- nally, to frequently change the moulds and thearms without interrupting the manufacture.

BRIEF SUMMARY OF THE INVENTION For this purpose the invention provides arotary assemblage with four or more arms supporting moulds ormould-rotating devices, a charging station, a hearing station, and atleast two cooling stations.

FURTHER DESCRIPTION OF THE INVENTION In an advantageous construction theheating station includes a movable heater, for example a furnace,movable upon guide rails to a withdrawn position in which it iscompletely clear of the mould-supporting arms and moulds. Preferablyeach cooling station is upwardly removable and includes a hood forming acooling chamber which is vertically displaceable, for example by meansof pulleys with cables or chains.

The following description explains, by way of nonlimitative example, aform of construction of the machine in accordance with the presentinvention, with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE VIEWS IN THE DRAWINGS In the accompanyingdrawings:

FIG. 1 is a diagrammatic plan view of the machine according to theinvention provided with difierent moulds, and

FIG. 2 is a lateral elevation thereof.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Thus as represented inthe accompanying drawings the machine is constituted essentially by arotary assemblage with four or more arms I, rotatable about the centralaxis 2, and by four production stations disposed upon a circular path 3in such a manner that the arms provided with different moulds ormould-rotating devices travel to these different stations in succession.

According to a first characteristic of the machine forming the subjectof the invention the heating station is formed by a furnace 5 which ismovable, for example on rails according to the double arrow F, in such apath that in the withdrawn position (shown in continuous lines in thedrawings) it is completely clear of the corresponding mould supportthereby permitting the closing and opening of its doors.

A further characteristic of the invention consists in providing, outsidethe charging station 4 and the heating station 5, at least two coolingstations 6, 7 thus permitting the doubling of the cooling time,necessary in some instances. In case of non-use of the second coolingoperation this station may serve possibly for the changing of moulds orof arms without interruption of production. Special arm-carryingcarriages, which are not shown, permit the effecting of this operationin a very short time.

The cooling stations are characterised in that they are verticallyremovable, that is to say that their cooling hoods 6', 7', provided eachwith a slot 8 for engagement over the arms of the rotary assemblage, canbe displaced vertically in the directions of the double arrows F l byknown means such as, for example, pulleys with cables or chains, orjacks, or the like.

Thanks to this possibility of vertical removal of the hoods 6', 7 it ispossible to free completely the floor at the cooling stations whichfacilitates, in a beneficial manner, the changing of the moulds or thearms as well as the supply and removal of these elements with the aid ofmechanical means such as trucks.

It will well be understood that the different rotational motions of thearms, which may be straight or bent, as well as the movements of therotary assemblage, are effected and may be controlled by known means.

The machine which forms the subject of the invention may be utilised forthe manufacture of articles of plastics materials or analogousmaterials, particularly containers, tanks, packaging components, toys,septic tanks, elements for decoration, boxes, ventilation ducts, andanalogous articles.

What is claimed is:

1. A rotational casting machine capable of functioning continuously,comprising a rotary assemblage with at least four mold-supporting meansthereon, a charging station, a heating station, at least two coolingstations, means for rotating said assemblage about an upright axisbetween said stations so that said moldsupporting means dwell in saidstations, said heating station comprising a heater, means mounting saidheater for movement radially of said axis between a radially innerposition in which said heater encloses a said mold-supporting means anda radially outer position in which molds carried by said mold-supportingmeans can pass said heater, said at least two cooling stationscomprising hoods open at their bottom and each comprising a coolingchamber, and means to move said hoods vertically between an upperposition in which said hoods clear the molds carried by saidmoldsupporting means, and a lower position in which said hoods surroundthe molds carried by said moldsupporting means.

2. A machine as claimed in claim 1, the said hoods extending below themolds carried by said moldsupporting means in said lower position andhaving a slot on their radially inner side to receive saidmoldsupporting means in said lower position.

3. A machine as claimed in claim 1, in which said heater comprises anenclosure having doors on its radially inner side that swing aboutvertical axes to open and close the enclosure.

1. A rotational casting machine capable of functioning continuously,comprising a rotary assemblage with at least four mold-supporting meansthereon, a charging station, a heating station, at least two coolingstations, means for rotating said assemblage about an upright axisbetween said stations so that said mold-supporting means dwell in saidstations, said heating station comprising a heater, means mounting saidheater for movement radially of said axis between a radially innerposition in which said heater encloses a said mold-supporting means anda radially outer position in which molds carried by said moldsupportingmeans can pass said heater, said at least two cooling stationscomprising hoods open at their bottom and each comprising a coolingchamber, and means to move said hoods vertically between an upperposition in which said hoods clear the molds carried by saidmold-supporting means, and a lower position in which said hoods surroundthe molds carried by said mold-supporting means.
 2. A machine as claimedin claim 1, the said hoods extending below the molds carried by saidmold-supporting means in said lower position and having a slot on theirradially inner side to receive said mold-supporting means in said lowerposition.
 3. A machine as claimed in claim 1, in which said heatercomprises an enclosure having doors on its radiallY inner side thatswing about vertical axes to open and close the enclosure.